לא תתגודדו

From the time that the disciples of Shammai and Hillel grew in number, and they were disciples who did not attend to their masters to the requisite degree, dispute proliferated among the Jewish people and the Torah became like two Torahs. Two disparate systems of halakha developed, and there was no longer a halakhic consensus with regard to every matter.

From the time when women with “stretched-forth necks and wanton eyes” (Isaiah 3:16) proliferated, the bitter waters of a sota proliferated, as more people were suspected of committing adultery; but they eventually ceased when licentiousness became too widespread. From the time when those who accept gifts proliferated, the days decreased and the years shortened, as it is written: “And he who hates gifts lives” (Proverbs 15:27). From the time when those with boastful [zeḥuḥei] hearts proliferated, dispute proliferated in Israel. From the time when the students of Shammai and Hillel who did not serve their Rabbis sufficiently proliferated, dispute proliferated in Israel, and the Torah became like two Torahs. From the time when those who accept charity from gentiles proliferated, the Jewish people were above and they below; the Jewish people ahead and they behind. This last statement is a euphemism; it was the Jewish people that were below and behind, but the Gemara did not want to say so explicitly.

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You are children: It is clear that this is an introduction and that the reason for the prohibition is after it. But it is difficult - if it is the reason, why did the Torah write another reason, "since you are a holy nation"... In the warning against lacerating yourselves there are two distinct meanings, as explained in Yevamot (13b): Do not lacerate your flesh in mourning for the deceased, and do not make separate groups. This is not an allusion, but the meaning of the text … including within this warning is that you should not have two Beit Din courts in a single city. For this reason the verse first gave the explanation that you are sons of Hashem, and since you are sons of Hashem it is not appropriate that you appear as different groups in the customs of your Torah, because the nature of children is to follow the same path.

MISHNA: In a place where the people were accustomed to perform labor on Passover eve until midday, one may do so on that day. In a place where the people were accustomed not to perform labor, one may not do so. The performance of labor on the eve of Passover is not prohibited by Torah law, but is dependent on local custom. If one travels from a place where people perform labor on Passover eve to a place where people do not perform labor, or from a place where people do not perform labor on Passover eve to a place where people perform labor, the Sages impose upon him the stringencies of both the place from which he left and the stringencies of the place to which he went. In both cases, he may not perform labor.

The Sages stated a principle: And a person may not deviate from the local custom, due to potential dispute. Similarly, one who transports Sabbatical Year produce from a place where a crop has ceased in the fields to a place where it has not yet ceased or from a place where it has not yet ceased to a place where it has already ceased is obligated to remove the produce from his possession, in accordance with the stringencies of both locations. It is permitted for homeowners to eat Sabbatical Year produce in their houses only as long as that species of fruit remains in the field as ownerless property. However, once that particular fruit is no longer available for animals in the fields, one is required to remove what remains of that species from his home. The statement in the mishna is referring to one who transported fruit from a location where it ceased in the fields to one where it did not, and vice versa. Rabbi Yehuda says that he need not remove the produce, as he can say to a local resident: You, too, go out and bring this produce from a place where it remains in the field.